Magnetic resonance imaging (MRI), or nuclear magnetic resonance imaging (NMRI), is primarily a noninvasive medical imaging technique used in radiology to visualize detailed internal structure and limited function of the body. MRI and NMRI devices are examples of a class of devices called magnetic response devices (MRD).
Objects to be analyzed are positioned within an MRI device in a predefined specific location and configuration. It is advantageous to adjust the location of the animal under inspection within the MRI device to obtain optimal analysis. Few patents pertain to means and methods of positioning analyzed objects. Hence for example, U.S. Pat. No. 5,066,915 discloses an RF coil positioning device for an MRI device in which a pallet is movably mounted on a mount and is moved by a drive means so that an RF coil unit mounted on the pallet is moved from its initial position at an imaging position in a magnetostatic field generator, the coil positioning device comprising: coil detecting means provided at a predetermined position along a path of the pallet, for detecting the passage of the RF coil unit through a reference position on the path and generating a detection signal, the distance between the reference position and the imaging position being preknown; distance detecting means for detecting the distance of travel of the pallet; and drive control means supplied with signals from the coil detecting means and the distance detecting means, for controlling the drive means to move the pallet until the distance of its travel after the generation of the detection signal becomes equal to the distance from the reference position to the imaging position; wherein the coil detecting means is provided below the underside of the pallet. Likewise, US patent discloses a diagnostic table for a medical imaging apparatus, the table comprising: a supporting unit; a tabletop movably supported by the supporting unit; a sliding command input device configured to receive a sliding command input, and generate a sliding command instruction corresponding to the sliding command input; a driving device configured to slidably move the tabletop in response to the sliding command instruction; a detector configured to detect actual sliding movement of the tabletop; a controller configured to compare the actual sliding movement of the tabletop with the sliding command instruction, the controller being configured to generate a fault condition instruction when the actual sliding movement of the tabletop is inconsistent with the sliding command instruction; and a stopper provided on the supporting unit and configured to be activated in response to the fault condition instruction in order to inhibit sliding movement of the tabletop. The MRI operator in those MRI systems cannot routinely, quickly and easily switch between one object to another, and between one type of object to other object.
Few patents disclose MRI devices with multiple apertures in the magnet structure. Hence, U.S. Pat. No. 5,490,513 discloses a medical magnetic resonance imaging system comprising: (a) a magnet having an imaging volume and at least two apertures thereto, each of the apertures providing patient access to the imaging volume; (b) at least two patient handling systems, each of the patient handling systems comprising a motorized and remotely-controlled bed structure which accesses a respective one of the apertures of the magnet, each of the bed structures having means for positioning the breast region of a respective patient for a magnetic resonance imaging procedure in the imaging volume of the magnet; (c) a radio frequency antenna system for transmitting radio frequency energy into each of the respective patients when in the imaging volume, and detecting magnetic resonance imaging data from the breast region of each the patient; and (d) automatic patient sequence control means for automatically sequencing the transfer of the respective patients into and out of the imaging volume. Likewise, U.S. Pat. No. 5,623,927 discloses a medical magnet resonance imaging system comprising: (a) a magnet having an imaging volume and at least two apertures, wherein each aperture is sufficiently large to provide patient access to the imaging volume; (b) at least two patient handling systems, with each of the patient handling systems comprising a moveable bed structure having means which provides access to one of the apertures of the magnet and with each of the moveable bed structures having means for receiving and positioning the breast region of a patient to be subjected to a magnetic resonance imaging procedure in the imaging volume of the magnet; (c) a radio frequency antenna system for transmitting radio frequency energy into a patient and detecting magnetic resonance imaging data from the breast region of each the patient. Scanned objects according to those patents are not maneuverable within the MRI device. Fine tuning of the various shape, size and type objects, especially in laboratory routine, wherein a frequent switching of scanned objects of different type shape and size is practically impossible utilizing those MRI systems.
None of the above provides a simple solution for routine insertion of more than one maneuverable small and tangible objects, such as laboratory items (microplates laboratory animals etc), within a single lab-scale experimental MRI device. Hence an MRI device with a plurality of individually controllable entry ports and MRI-compatible inserts therefor fulfill a long felt need.